1. Field of the Invention
The present invention relates to a displacement sensor configuration, and more particularly to a displacement sensor configuration that optically detects a displacement of a scale light imaging configuration relative to a scale grating.
2. Related Art
There is disclosed an encoder that optically detects a two-dimensional displacement of a scale light imaging configuration relative to a one-dimensional scale grating (see U.S. Pat. No. 7,601,947). Its structure, however, is very complicated.